I would use Davis RF Buryflex cable and I would put it inside polypipe,
the good old stuff that sprinklers are used with; but I would just put
the ends much higher than the pond, and seal it. I think that this
would work out really nice and Davis RF is a great company to deal with.
This way when your pond freezes, the compression will be against the
polypipe and not against the actual RF cable. I wish you the best of
luck and I have used a bunch of this on my tower successfully and it is
some really bullet proof cable. I got burned a few years back by buying
Belden 9913 within a couple of years, it all failed. Some of the worst
cable I have ever owned, so it taught me my lesson about "you have to
have a name brand!" 73's Gene K2QWD
-----Original Message-----
From: owner-towertalk@contesting.com
[mailto:owner-towertalk@contesting.com] On Behalf Of WA9ALS - John
Sent: Tuesday, October 23, 2001 7:00 AM
To: towertalk@contesting.com
Subject: [TowerTalk] Underwater coax
I don't want to start a debate about whether this is a good idea, or
which
coax would be best. However, I would like some ideas about how to
handle
the points where the coax enters and exits the water.
I'm going to run a feedline across a pond that the top 10-12 inches of
which
freezes each winter. Someone said I should use some PVC where the coax
enters and exits the water to relieve compression forces at the freeze
line.
I can't picture how to do this - Seems like if I just put a PVC pipe
there,
it will fill to the surface level with water, and then that water inside
the
PVC will also freeze. And it seems the compressive force from the ice
outside the PVC would translate through the pipe, through the ice inside
of
the pipe, and finally to the coax. Is there something I'm missing about
how
to do this with PVC pipe at the entrance and exit points?
I suspect it would be functional for "quite a while" if I just let the
coax
take whatever nature has to offer, and it will be easy to replace if
needed
every few years (except for those "crappy PL-259s"!). But if there's
something reasonable to do to protect it some more, I'd like to do it.
Please read the first paragraph of this again, and then I'd be grateful
for
any constructive ideas. Thanks!
------------------------------------------------------------
John - WA9ALS - VP5RY
email: wa9als@starband.net
homepage: http://www.qsl.net/wa9als (New - NCJ article on VP5 trip)
List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
Trylon Titan towers, coax, hardline and more. Also check out our self
supporting towers up to 100 feet for under $1500!!
http://www.anwireless.com
-----
FAQ on WWW: http://www.contesting.com/FAQ/towertalk
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
Trylon Titan towers, coax, hardline and more. Also check out our self
supporting towers up to 100 feet for under $1500!! http://www.anwireless.com
-----
FAQ on WWW: http://www.contesting.com/FAQ/towertalk
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
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